WR450 overheating


12 replies to this topic
  • sjclark

Posted August 08, 2007 - 10:55 AM

#1

My bike overheats, when I'm doing a lot of real slow technical riding, such as uphill rocky climbs in 1 to 2nd gear. I've rejetted to a slightly richer mixture, and put Engine Ice in it. Ive also opened up the muffler, and regeared. Is there any thing substancial that could be done to make it run cooler. I was thinking of a KTM radiator fan.:prof:

  • bg10459

Posted August 08, 2007 - 11:03 AM

#2

If you're doing lots of slow, technical riding and you can't keep fluid in your rads, you are a perfect example of someone who can benefit from Evans NPG+. You won't really run cooler, but you won't puke coolant.
Of course, you must first determine that there are no underlying problems like a blown head gasket or cracked water jacket.

  • ghunter

Posted August 08, 2007 - 02:39 PM

#3

My WR450 also runs hot in SoCal summer weather when riding slow technical trails. I purchased two high-volume computer fans, made an aluminum bracket for each radiator, and wired them to a switch on my handlebar and then into the factory wiring harness. The fans run on the bikes generator only when running - i.e. not wired to the battery - so there is no chance of leaving them on and draining the battery. If I'm not running slow trails I just hit the switch (if I remember) and turn them off.

After a high-speed run without the fans, I've parked the bike and let it idle with the fans on and seen temps drop 12-15 degrees (using temp strips on the top and bottom of the rads) within a few seconds. Without the fans on the temps increase at idle. As I don't have a temp gauge that I can see when riding, I can't tell what these do when moving fast but they sure work well when riding slow or idling.

  • Sycamore

Posted August 08, 2007 - 02:57 PM

#4

My WR450 also runs hot in SoCal summer weather when riding slow technical trails. I purchased two high-volume computer fans, made an aluminum bracket for each radiator, and wired them to a switch on my handlebar and then into the factory wiring harness. The fans run on the bikes generator only when running - i.e. not wired to the battery - so there is no chance of leaving them on and draining the battery. If I'm not running slow trails I just hit the switch (if I remember) and turn them off.

After a high-speed run without the fans, I've parked the bike and let it idle with the fans on and seen temps drop 12-15 degrees (using temp strips on the top and bottom of the rads) within a few seconds. Without the fans on the temps increase at idle. As I don't have a temp gauge that I can see when riding, I can't tell what these do when moving fast but they sure work well when riding slow or idling.



What brand fans did you get and where did you get them?

  • ghunter

Posted August 08, 2007 - 06:50 PM

#5

I used these and purchased from the same site:

http://www.newegg.co...N82E16811999613

For a PC they are loud as hell, but you can't even hear them at idle on my WR, and certainly not at any higher RPM. These things move LOTS of air - 120cfm. If your temps aren't terrible, you might skip the right side fan as it will blow on the lower part of the gas tank. I haven't had any problems with fuel boil, but it is something to think about...

I need to clean my carb tomorrow so I'll post some pics of the setup once I get the tank off...if I remember. If I forget, send me a PM or something.

Gregg

  • Jwar1r1t3

Posted August 08, 2007 - 07:05 PM

#6

I would really like to see the wiring you did with the fans. And exactly how you mounted them. I am definitely doing some type of fan and want to wire it correctly. Thanks

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Team_Oatmeal_Pie

Posted August 08, 2007 - 11:12 PM

#7

I run the Boyesen water pump, and have been very happy with it (in AZ)
It cant get crushed or gummed up with mud like a fan can.

  • BIG HAL

Posted August 09, 2007 - 08:09 AM

#8

No need to buy fans!! If that was an issue then Yamaha would have used them.. Go to a 50 pilot and bring the fuel screw out 2 1/2 or 3 turns and she'll be happy!! I ride mine in the woods on trail rides and it doesn't overheat after I went richer and no more pipe glow either..

  • ghunter

Posted August 09, 2007 - 01:55 PM

#9

Where I ride in SoCal it can easily hit 115 in the summer, so while spot-on jetting is good for the power and throttle response it won't do a damn thing to make the bike run any cooler unless it is already running lean to begin with. This brought about the installation of the fans WHICH ARE NEEDED where I ride during the summer. Of course there are other ways around this overheating, but for the cost of two fans @ $10 each and a sheet of aluminum for a bracket, it sure is cheaper than many of the alternatives I have seen, i.e the Boyeson water pump cover for $189+tax.

As a side effect, my bike runs cooler all around with lower overall operating temps which could possibly allow greater longevity to the motor oil, thus increasing the life of the engine itself. As heat is a horsepower killer, lower temps could even allow the bike to produce more power...just a few thoughts to justify fan installation.

As for mud getting in the fans...

First off, the fans are mounted behind the rads so there is very little chance of mud getting on them. Second, I would be happy to FIND mud in SoCal in the Summer, or Spring or Fall for that matter. The only time I would expect to see rain - let alone mud - is in the middle of Winter when I wouldn't need the fans anyway as it would be cooler. Ten minutes of wrenching and the fans would be removed so I can save them until next Summer.

Finally, just because Yamaha didn't install fans from the factory doesn't mean these bikes don't need, or cannot benefit from, additional cooling. How many folks install larger fuel tanks, steering stabilizers, different suspension springs or valving, aftermarket exhaust systems, JD Jetting kits, etc. I guess none of those things are needed either, huh?

  • ckroto

Posted August 09, 2007 - 02:47 PM

#10

I second that ghunter, it gets too damn hot to do nothing about cooling here in AZ. Some of our trails are technical and slow, so a little addition of a fan works great.

  • Bat-450

Posted August 09, 2007 - 10:51 PM

#11

I tried "engine ice" - still overheated. Then I bought the expensive fluidyne larger capacity radiators - still overheated. Finally I tried going with straight anti-freeze - problem solved! (here in Hawaii we dont have to worry about anything freezing:ride: ) Just my 2 cents...

  • albertlui

Posted August 10, 2007 - 04:28 AM

#12

My WR450 also runs hot in SoCal summer weather when riding slow technical trails. I purchased two high-volume computer fans, made an aluminum bracket for each radiator, and wired them to a switch on my handlebar and then into the factory wiring harness. The fans run on the bikes generator only when running - i.e. not wired to the battery - so there is no chance of leaving them on and draining the battery. If I'm not running slow trails I just hit the switch (if I remember) and turn them off.


May I know which point you connected into? Your fan is 12VDC, right? If not the battery side, it will be more than 14VAC. Can it work with AC? I am also thinking how to connect a fan.

  • ghunter

Posted August 10, 2007 - 07:07 AM

#13

There is a red wire in the wiring harness just under the tank. This is the wire coming from the charging system to the battery to keep it charged. I had already disconnected this from the battery as I am using an Ebatt (see http://www.ebattonline.com for details ) instead of a regular battery.

Edit - here are links to a few pics.

This link shows how the fan looks while bike is assembled:
http://home.socal.rr...es/DSC01460.JPG

This shows the fan mount with the shroud removed:
http://home.socal.rr...es/DSC01461.JPG

This shows the $4 switch I used:
http://home.socal.rr...es/DSC01463.JPG

This shows the connector I wired into:
http://home.socal.rr...es/DSC01464.JPG

Gregg




 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.